Fluid flow control device with baffles

ABSTRACT

A fluid flow control device of the flexible diaphragm valve type includes a plurality of baffles mounted on the surface of the diaphragm facing the valve seat and extending radially from the centerpoint of the diaphragm. The disclosed fluid flow control device has a reduced pressure drop and greater capacity.

United Staies Patent 11 1 1111 3,762,681

McKinney et a1. Oct. 2, 1973 I541 FLUlll) FLOW CONTROL DEVHCE WITH3,078.066 2/1963 Moore 251K015 X 2,487,501 11/1949 Williams.... 351/611X BAFFLES 3,468,511 9/1969 Haskius 1251/61.] 1 Inventors: Richard W.McKinney; J y 3.275911 9/1966 Berezansky 251 331 x Katclilm; Fred W.Ellendriek, all of Long Beach, Calif. [73] Assignee: Robcrlslmw11311111111115 Company, :Z g g, 9

Richmond Va. 0rneyrenner, men an may [22] Filed: Sept. 28, 11971 [21]Appl. No.: 184,388 I57] ABSTRACT 152] US. Cl 251/61.1, 137/510, 251/331A fluid flow control device of the flexible diaphragm [51] 1111. C1.F1611 7/17 valve type includes a plurality of baffles mounted on [58]Field 011 Search 25 the surface of the diaphragm facing the valve seatand 251/3 37/510 extending radially from the centerpoint of thediaphragm. The disclosed fluid flow control device has a [56] ReferencesCited reduced pressure drop and greater capacity.

UNITED STATES PATENTS 3.426.798 2/1969 Chcruak 251/331 X 1 Claim, 5Drawing Figures PATENIEU 21973 3.762.681

INVENTORS M NNEY R. KATCH D W. HENDRICK FLUID FLOW CONTROL DEVICE WITHEAFFLES BACKGROUND OF THE INVENTION 1. Field of the Invention Thisinvention relates generally to fluid flow control devices, such aspressure regulators, and more particularly to flexible diaphragm valvesfor regulating main gas pressure to fuel burners.

2. Description of the Prior Art Various designs for diaphragm valveshave been suggested in the prior art for the purpose of reducing thepressure drop across such valves. This is due to the fact that a designwhich produces a higher pressure drop across the valve results in areduced fluid flow through such a valve or alternatively requires ahigher inlet pressure for a given fluid flow. Expressed in another way,the capacity of such a valve is reduced by a relatively high pressuredrop. Examples of valves of the prior art are disclosed in U.S. Pat.Nos. 1,964,921; 2,211,212; 2,307,066; 2,394,911; 3,282,556; 3,468,511and 3,502,300.

SUMMARY OF THE INVENTION The present invention is embodied in a fluidflow control device which includes the combination of a valve casinghaving inlet means and outlet means and an annular valve seattherebetween having a predetermined radius from its centerpoint, a valveface adapted to cooperate with the annular valve seat, and severalbaffles or vanes fixedly mounted on the surface of the valve face andextending radially from a point on the valve face correspondinggenerally to the centerpoint of the annular valve seat, the terminalportion of each of the baffles extending a distance less than the radiusof the annular valve seat.

An object of the present invention is to provide a flexible diaphragmvalve having a reduced pressure drop between its inlet and outlet.

A further object of the present invention is to provide a flexiblediaphragm valve having increased capacity and providing greater fluidflow for a given inlet pressure.

Other objects and advantages of the present invention will becomeapparent from the following description taken in conjunction with theaccompanying draw- BRIEF DESCRIPTION OF THE DRAWING FIG. 11 is aschematic diagram with parts in section of a gas flow control system inwhich the present invention may be embodied;

FIG. 2 is a top plan view of a diaphragm incorporating one embodiment ofthe present invention;

FIG. 3 is a cross-section of the embodiment of the present inventionshown in FIG. 2 taken along line 3-3 of FIG. 2;

FIG. 4 is a top plan view of a diaphragm incorporating a secondembodiment of the present invention; and

FIG. 5 is a cross-section of the embodiment of the present inventionshown in FIG. d, taken along line 55 of FIG. 4.

DESCRIPTION OF THE PREFERRED EMBODIMENT A pressure regulator I having anupper section 112, a central section 14, and a lower section 116 isillustrated in FIG. 1. Section 12 includes a bleed pressure regulator 18and an actuator 20 in the form of an on-off and/or a modulating controldevice, both of these components being of conventional design and hencebeing represented schematically in FIG. 1. Actuator 20, which may be avalve, is operated in response to conditions sensed by thermal bulb 22and communicated to the actuator by capillary tubing 24 A bleed chamber26 is situated in the interior of section 112 and a layer of gasketingmaterial 27 is placed between sections 12 and il -ll to create afluid-tight seal.

Section 14- includes an inlet passage 28 and an outlet passage 30 thatare separated by an annular valve seat 32. A flexible diaphragm 34 (ofconventional design in FIG. 11) cooperates with seat 32 to control thefluid flow therethrough. Diaphragm 34 includes a raised generallycircular valve face or wall 35 disposed on and forming an integral partof diaphragm 34. Circular wall 35 extends substantially transverselyfrom the surface of diaphragm 34 toward valve seat 32 and has a diameter greater than that of valve seat 32. The periphery of valve 3d isclamped between sections 14 and 16 during the assembly of regulator 10.The central part of the diaphragm encloses an upwardly opening cavity insection 16 to create an operating chamber 36 on its underside. Thecentral part of the diaphragm also separates chamber 36 from inletpressure chamber 38 created within section M on its opposite side.

Inlet chamber 38 communicates with inlet passage 28 so that the uppersurface of the diaphragm valve is subjected to inlet pressure. Abackupplate or washer pan 40 is secured to the underside of diaphragm 34by forcing the pan into the annular rib of a projection 41 dependingfrom the center of diaphgram 34. A coil spring d2 is mounted incompression between the bottom wall of the cavity in section 116 and thepan whereby valve 3 1 is biased toward valve seat 32.

Regulator 110 has an internal bleed line arrangement including an inletbleed passage 44 which communicates with main flow inlet passage 23 andwhich leads to the bleed chamber 26 having divergent bleed passagesleading therefrom. A flow restrictor 416 with an small orifice thereinis disposed in passage 44 to cause a pressure drop in the bleed flow.One divergent passage 40 leads from chamber 26 to operating chamber as,and another passage (not shown) leads from chamber 26 through on-offactuator 20 and bleed pressure regulator 13 and thence through an outletpressure sensing port to outlet passage 30 to establish communicationtherebetween.

The operation of a valve of the type illustrated by regulator 10 is wellknown in the art, being described in detail, for example, in U.S. Pat.NO. 3,468,511. The open position of main valve 341 of regulator 10 isshown in FIG. 11 wherein the valve is moved'downwardly away from seat 32under normal, relatively high flow rate conditions.

One of the embodiments of the present invention is illustrated in FIGS.2 and 3. In this embodiment four baffles or vanes 50, 52, 54 and 56 aremounted on circular wall 35 which is fixedly mounted on diaphragm 34.Baffles S0, 52, S4 and 56 extend radially from the centerpoint ofcircular wall 35 and diaphragm 34, which corresponds normally to thecenterpoint of valve seat 32. Baffles 50, 52, 54 and 561 are spacedapproximately degress apart and extend radially outwardly from thecenterpoint a distance less than the radius of valve seat 32. Thus whendiaphragm 34 is in a closed position baffles 50, 52, 54 and 56 will bedisposed within the interior of valve seat 32 which engages circularwall 35. The baffles 50, 52, S4 and 56 are each tapered slightlyoutwardly from top to bottom on their outer edges.

The preferred embodiment of the present invention is illustrated inFIGS. 4 and 5. in this embodiment baffies or vanes 60, 62, 64 and 66 arefixedly connected to a hollow frusto-conical member 70, all of whichelements are fixedly mounted on circular wall 35 which in turn ismounted on diaphragm 34. Conical member 70 is mounted approximately atthe centerpoint of circular wall 35 and diaphragm 341, which correspondsnormally to the centerpoint of valve seat 32. Thus, the longitudinalaxis of conical member '76 is generally perpendicular to the plane ofdiaphragm 34 and intersects the centerpoint of diaphragm 34. Baffles6t), 62, 64 and 66 are spaced approximately 90 apart and extend radiallyoutwardly from the centerpoint of conical member 70. The outer ends ofbaffles 60, 62, 64 and 66 extend from the centerpoint of conical member70 a distance less than the radius of valve seat 32. Thus, whendiaphragm valve 34 is in its closed position, conical member 70 andbaffles 60, 62, 64 and 66 connected thereto are disposed within theinterior of valve seat 32 which engages circular wall 35. The baffles60, 62, 64 and 66 are tapered slightly outwardly from top to bottom.Diaphragm 34 also includes in this embodiment an annular tab 72 whichprovides a sealing means for bleed gas ported to the underside of thediaphragm 34, as is conventional in this type of pressure regulator.

A cylindrical interior cavity 74 of conical body member 70 extends fromthe top of conical member 70 down to a point corresponding generally tothe bottom of circular wall 35 and the top of projection 41. In thisparticular embodiment of the present invention, projection 41 isprovided with a cylindrical interior cavity 76, as is best illustratedin FIG. 5. Cavity 76 is of lesser diameter than cavity 74 and is axiallyaligned therewith and with the longitudinal axis of conical member 70.

It has been found that the several baffles, or plurality of baffles,provided in accordance with the present invention significantly increasethe fluid flow through pressure regulator 116. it is believed, withoutwishing to be found by theory, that these results are achieved by theaction of the several baffles or vanes which reduce turbulence, swirlsand eddy currents of the fluid flowing through regulator 10. Theseresults are particularly desirable in that low main gas line pressuresare required. Also the use of smaller pressure regulator and valvecomponents are required for a given rate of fluid flow. Further, thepresent invention makes it possible to secure a higher capacity withoutenlarging the size of the control body.

Inasmuch as the present invention is subject to many modifications,variations and changes in detail, it is intended that all mattercontained in the foregoing description or shown in the accompanyingdrawings shall be interpreted as illustrative and not in a limitingsense.

What is claimed is:

l. In a gas flow pressure regulator, the combination comprising a valvecasing having inlet and outlet means and an annular valve seattherebetween,

a differential pressure operated diaphragm made of flexible rubber-likematerial and being disposed upstream of said valve seat,

said diaphragm having a peripheral portion mounted in said casing and acentral portion defining a valve face cooperating with said valve seatto regulate pressure of a gas flow therethrough,

a frusto-conical member integrally formed on said central portion andextending through said valve seat so as to have its free end portiondisposed downstream of said valve seat,

a plurality of equally spaced baffles integrally formed on said centralportion and said frusto-conical member.

said baffles having free end portions terminating with the free endportion of said frusto-conical member so as to extend through said valveseat and be disposed downstream of said valve seat to reduce turbulenceof the gas flow to said outlet means, and

a centrally disposed cavity in said frusto-conical member being open atthe free end portion thereof whereby said cavity is open downstream ofsaid valve seat.

a a a x:

1. In a gas flow pressure regulator, the combination comprising a valvecasing having inlet and outlet means and an annular valve seattherebetween, a differential pressure operated diaphragm made offlexible rubber-like material and being disposed upstream of said valveseat, said diaphragm having a peripheral portion mounted in said casingand a central portion defining a valve face cooperating with said valveseat to regulate pressure of a gas flow therethrough, a frusto-conicalmember integrally formed on said central portion and extending throughsaid valve seat so as to have its free end portion disposed downstreamof said valve seat, a plurality of equally spaced baffles integrallyformed on said central portion and said frusto-conical member. saidbaffles having free end portions terminating with the free end portionof said frusto-conical member so as to extend through said valve seatand be disposed downstream of said valve seat to reduce turbulence ofthe gas flow to said outlet means, and a centrally disposed cavity insaid frusto-conical member being open at the free end portion thereofwhereby said cavity is open downstream of said valve seat.